Gas-liquid chromatography (GLC), or simply gas chromatography (GC), is a common type of chromatography used in 
organic chemistry for separating and analyzing compounds that can be vaporized without decomposition (source: wikipedia.org). In anesthesiology, GC has often been considered the most accurate method to measure the concentration of inhaled anesthetic vapors.
One of BMC Anesthesiology Journal published on February 2008 reviewed topic about comparing the accuracy of infrared (IR) gas analysis (M-CAiOV) which has become the clinically preferred monitoring technique because of its continuous data, less expensive, readily available. and more practical with the performance of Gas Chromatography.
The researchers examined 3 different concentrations of 3 different agents in O2: 0.3, 0.7, and 1.2% isoflurane; 0.5, 1, and 2% sevoflurane; and 1, 3, and 6% desflurane. To examine the effect of carrier gas composition, they prepared mixtures of 1% isoflurane, 1 or 2% sevoflurane, or 6% desflurane in 100% O2 (= O2 group); 30%O2+ 70%N2O (= N2O group), 28%O2 + 66%N2O + 5%CO2 (= CO2 group), or air. Consistency between analyzers were tested by four different M-CAiOV analyzers.
Jan FA Hendrickx from Department of Anesthesia, Stanford University School of Medicine, Stanford, California, USA and his colleagues were particularly interested in the performance of the M-CAiOV unit because its ability to measure vapor concentrations and therefore studied the performance of 4 units, and examined whether IR accuracy approaches that of GC.
And they described in the conclusion that M-CAiOV compact gas IR analyzers are well compensated for carrier gas cross-sensitivity and linear over the range of concentrations studied. However, IR and GC cannot be used interchangeably, because individual analyzers differ unpredictably in their performance.
See more complete information about Infrared Gas Analyzer Instead of Gas Chromatography, an Accuracy Comparing in Full PDF type (source: pubmedcentral.nih.gov).
